Clark County Nevada, which includes Las Vegas, and the surrounding areas, has failed to achieve compliance with the health-based pollution standards set by the U.S. Environmental Protection Agency (EPA). These standards, called National Ambient Air Quality Standards (NAAQS), set acceptable ozone concentrations allowed in the air. Because Clark County has not met the ozone NAAQS, it is required to develop and impose new regulations designed to reduce the precursors of ozone, which are Volatile Organic Compounds (VOC) and Nitrogen Oxides (NOx).